Play Halo 2 on PC..., sure!!!, but buy VIsta to play this game, I dont know!?. If Bungie thinks making Halo 2 compatible with XP, excellent!!, because I dont understand why I need Vista to run Halo 2 if it doesnt uses DX10. Why dont make Halo 2 like STALKER or Test Drive Unlimited, these games run in XP and Vista and will only need a patch for run the game with DX10(someday). PD: Sorry for my english!